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2 Sheets-Sheet; t.

(No Model.)

T. e. 'ELLSWORTH Telephone Cent-rel Office Apparatus. No. 240,983.

Patented May 3,1881;

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ATTORNEYS.-

N. PETERS. PHOTO UTHOGRAPHER WASHINGTON, D. C.

2 SheetsSheet 2.

(No Model.)

Patented May 3 la La 5 iii- La La c INVENTOR:

ATTORNEYS.

N. PETERS. PHOTU-LITNOGRAFHR, WASHlNGTON. D. C.

UNTTE STATES PATENT OFFICE.

T. GARDNER ELLSWORTH, OF NEW YORK, N. Y.

TELEPHONE CENTRAL-OFFICE APPARATUS.

SPECIFICATION forming part of Letters Patent No. 240,983, dated May 3, 1881, Application filed April 28, 1880. (No model.)

To all whom it may concern:

Be it known that I, T. GARDNER ELLs- WORTH, of the city, county, and State of New York, have invented a new and ImprovedTelephone Oentral-Office System and Apparatus, of which the following is a specification.

The object of this invention is to facilitate connection between wires of tclephone-linesin a telephone central office, and to afford means for making such connections rapidly and accurately.

Ordinarily in telephone central offices mistakes and delays in connecting and disconmeeting the wires of comm unicating parties are of frequent occurrence, for the reason, among others, that the operator at the telephone cannot conveniently, or does not himself, connect and disconnect the wires, but gives directions to others to do so 5 hence results much noise and confusion, and consequent misunderstandin g and forgetfulness or neglect of orders.

To avoid these difficulties Ihave invented asystem involving the use of novel switch-connections and of novel telephone-stands and their peculiar arrangement relative to each other, whereby each telephone-operator is enabled easily and without delay to connect and disconnect several communicating wires that are connected with his instrument.

Figure l is a perspective view of my improved device as appliedin acentral telephoneoftlce. Fig. 2 is a longitudinal sectional view of the switchboard, showing the rear connections. Fig. 3 represents a front and edge view of the improved connections. Fig. 4: is a sectional side elevation of theimproved telephone-stand. Fig. 5 is a diagram representing the construction of the connections, and Fig. 6 is a front elevationofonesetofconnecting-plates. Figs. 7 and S are respectively a side view and crosssection of the switch detached from the switchboard. Fig. 9 is a perspective view of the parts composing the annunciator.

Similar letters of reference indicate corresponding parts.

One of the principal features of my invention is the device by which connection is effected between two or lnorelines terminating in the central oflice. This device, or connector, as I have termed it, consists of a series of wires, D, secured to a board, A, and attached at intervals to metal plates 0. The plates are arranged in horizontal and vertical rows, and in practice willgenerally be dividedinto groups or sections, asshown in Figs.1, 2, and 3. Each wire is connected with one plate in each section or group. For example, the upper wire D is connected with the upper left-hand plate 0 in each section. The second wireD is connected with the middle plate 0 in the upper row in each section, and the third wire is connected with the right-hand plate in the upper row in each section. The fourth wire Dis connected with the left-hand plate in the second row in each section, and so on. These connections occupy but little space and are very inexpensive in their construction.

A wire, E, connects either or both ends of the wire D with a telephone, F, and series 'of telephones F are located in a central office at the most suitable distances from the switchboard A, and opposite the annunciator and switch-sections, for the purpose of rapid manipulation of the switch-plugs in the process of connecting and disconnecting communicating wires.

Above the switch-board A are fixed series of ordinary plug-switches, G, connected with the line-wires eXten din gto subscribers telephones. These switches are connected with ordinary annuncia-tors, H, located still higher up, and one terminal ofeach annunciator-magnetis grounded, so that each subscribers telephone-line has its own switch and annuncia-tor, and is grounded through the annunciator.

The switch employed is what is commonly termed tlie,jack-knife. As shown in Figs. 7 and 8, it consists of a longitudinally-slotted bar, a, and a bar, I), hinged thereto. The bar a has transverse holes and one or more screwbolts, 0, for attaching it to the switch-board. The arrangement is such that when a tapered plug is inserted in either of the holes in bar a the bar I) will be turned on its hinge so as to separate the points d, and thus break the circuit through the annunciator.

The telephone-stand M holds one or more complete telephones, Fthat is, a transmitter, receiver, and call-and all the connecting-wires are conducted inside of the hollow stand M, and are not exposed to view. The stand M consists of a base, m, a hollow standard, preferably rectangular and constructed in two sections, 11. o, united by tenon and socket, the face 11 of the lower section, a, being removable. The stand has a removable cap, q, which admits of adjusting the wires readily. The stand M is provided with as many switches 1 as the attendant can manage. In the presentinstance three are shown. One half of each switch I is connected with the telephone on the stand, and the telephone is grounded, in the usual way, through the wire K, and the transmitter is also connected with a battery, P, as shown. The other half of each switch is connected with one of the wires D on the board A by a wire, E, so that three of the wires D are connected with the three switches I on the telephone-stand M.

The operation of the system is as follows: For instance-Poe, desiring to converse with Park, signals to the central ofiice, and thereby drops the annuneiator H connected with his wire. The telephone-operator, seeing this, at once takes a pair of connected couplingplugs, N, and by inserting one of them in the switch G on the subscribers line cuts off the annunciator and the ground, and by inserting the other plug in one of the plates 0 connects the subscribers wire with one of the wires D, and consequently with one of the switches I on the telephone-stand M. Then the operator inserts a plug in the proper switch, I, and signals Poe by throwing the call-battery L into communication with the subscribers line by means of the call-key PI, connected with the said battery L and with the switches I. This causes a bell to ring at Poes office, to notify him to announce his wish to the telephone-operator at the central office. Poe then asks to be connected with Park; then the operator at once connects Park with Poe on the same wire D by inserting a plug, N, in the plug-switch G connected with Parks wire, and inserting the connected plugN in one of the plates 0 con nected with the same wire D. The operator calls Park bymeans of the call-batteryLandinforms him that Poe desires to speak with him. The telephone F and ground K are then cut out of the circuit by the operator by removing the plug from the switch I, when Poe and Park are connected as by a private wire. About once a minute the operator closes the circuit by inserting the plug in the switch I long enough to determine if the parties are still conversing. On discovering that they have finished talking he disconnects them by withdrawing the plug N.

Each operator connects and disconnects all the subscribers that he answers at the central office, and hence there are but few, if any, such delays or mistakes as are common to other telephone-exchange systems. The telephones are placed within easy reach-a step from the switch-board-so that operators can work rapidly and without interference, and the switchconneetions O and wires D are so compactly and conveniently arranged that one operator can keep three or more connectors in operatian at the same time.

After opening the circuit of the connector used by Poe and Park, for instance, the operator will close the circuit of another connector and bring two other parties in communication with each other, and so on with third and fourth parties, care always being exercised to disconnect when parties have finished conversin g.

In describing my improved switch-board l have mentioned the combination of the wires D with plates 0; but I do not limit or confine myself to the use of the plates 0, as I may use bolts or clamps or other devices answering the same purpose.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. In a telephone central-oflice system, the combination, with the isolated stand M and the telephonic instruments, switches I, and call-key Pl, placed thereon, of the.annunciators H and switches Gr, connected as shown, the switch-board A, having plates 0, connected by wires D and provided with holes or sockets, the flexible switch cord N, having terminal plugs, and the wires E, which connect said switch-board and the stand-switches I, all as shown and described.

2. In a telephone system and apparatus, the hollow telephone-stand M, constructed sub stantially as herein shown and described, consisting of base m, section at, having movable face 1), section 0, and cap 1, as set forth.

T. GARDNER ELLSWORTI-I.

Witnesses I. I. Sronna, (J. SEDewIoK. 

